Throat-plate for sewing-machines.



a. MUFHI'T. THROAT PLATE FOR SEWING MACHINES.

APPLICATION FILED OCT- 25 I915.

Patented Nov. 5, 1918.

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COMPANY, or eHIcaeojILLI IoIs, A; COBJPURATION or ILLIIvoIs.

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Original application filed January l, 1912, Serial No. 669,377, Divided and this application filed October 25,

Specification of Letters Patent.

Patented Nov. 5, 191%.

1915. Serial No. 57,726. 1

b all whom it may concern:

Be it known that 1, Jaime R. Morra'r'r, a citizen of the United States, residing at Chicago, in the countyof Cook State of Illinois, have invented certain new and use-- ful Improvements in Throat-Plates for Sewing-lt ilaohines, of which the following is a description, reference being had to the accompanying drawing and to the figures of reference marked thereon.

The invention relates to new and useful improvements in throat plates for sewing machines and more particularly to a throat plate adapted to be used in connection with a work supporting arm containing feeding mechanism and the complemental stitch forming mechanism cooperating therewith.

An object of the invention is to provide a throat plate which shall be strong and durable and which shall be so constructed as to permit the supporting part or parts of the feed dog which extend across the plane of movement of the looper to be positioned well above the path of travel of the looper and the looper located so as to move relatively close to the under side of the throat plate.

In the drawings, which show by way of illustration one embodiment of the ii1ven tion Figure 1 is a sectional view showing portion of the work support, a portion of the feeding mechanism, the presser foot, and my improved throat plate associated therewith;

Fig. 2 is a plan view of the same, the presser foot being omitted;

Fig. 3 is a bottom plan View of the throat plate;

Fig. 1 is a sectional view on the line a e of Fig. 1;

Fig. 5 is a perspective view of the auxiliary feed dog;

Fig. 6 is a perspective view of the main feed do and Fig. F is a detail in section showing the position of the looper, the needles, the throat plate and the feed dog supporting parts which cross the plane of movement of the looper.

My improved throat plate is adapted to be used in connection with a sewing machine having a cylindrical work support. The machine is shown and described in my copending application, Serial No. 669,377, filed January. 1912,.of which this application 1S adivision. i i i In Fig. 1 of the drawings, I have shown the forward end of 1 the cylindrical work support 1, in which is mounted a feed bar 2 carrying a feed dog 3. cylindrical shank 1 which is mounted 011 the outer end of this bar 2. This is the main feed dog of the machine. Also mounted to reciprocate on the bar 2 is a sleeve 5. Said sleeve 5 is formed with a head 6 carrying spaced bars 77, and at the forward end of said bars there is a cross piece 8 having feeding surfaces 9.

The feed bar 2 is moved up and down so as to carry both feed dogs into engagement with the fabric for the feeding movement and lower the same from engagement with the fabric for the return idle movement. The feed dog 9 may be given a differential movement, relative to the main feed dog. The main feed dog 3 extends between the side bars 77 which support the auxiliary feed dog. Cooperating with the feed dogs is a presser foot 10.

Mounted on the work support 1 is my improved throat plate 11. Said throat plate is provided with slots 12, 13 and 14 for the feed engaging surfaces of the feed dogs. Said throat plate is also provided with needle slots 15 for the needles a, which as herein shown are three in number. Cooperating with these needles beneath the work support is a looper Z. In a machine having a work supporting arm, it is very desirable that the looper shall have a path of travel which is relatively close to the under surface of the throat plate. This gives room for the pivotal supporting of the looper without unduly enlarging the work supporting arm. In order that the looper may be placed close to the under face of the throat plate I have provided said throat plate with recesses on said under face which are indicated at 16 and 17 of the drawings. These recesses are adapted to receive the side bars 77 of the auxiliary feed dog, that is the supporting parts of the feed dog which extend across the plane of movement of the looper. This permits the feed dog to be supported firmly and the throat plate to be made of suiiicient strength to be durable without interfering with the movements of the looper.

It is obvious that minor changes, may be.

This feed dog has a 1. A throat plate for sewing machines having a slot for the fabric engaging part of the feed dog and a recess on the under side thereof for the supporting part of the feed dog, said recess extending along one side only of the feed slot.

2. A throat plate'for sewing machines having needle slots formed therein and a slot ateach side of the needle slots for the fabric engaging parts of the feed dog, said 3 throat plate having recesses on the under side thereof for the supporting parts of the feed dog, said recesses being disposed respectively along one side only of the slots for the fabric engaging parts of the feed dog r andron oppositesides of the feed slots from the needle slots.

In testimony whereof, I aflix my signature in the presence of two witnesses.

JAMES R. MOFFATT.

Witnesses GEORGE TATE, R. S. KELso.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

- g Washington, D. 0. 

